The Home Phone Line Network association (HomePNA) has established various standards which allows networking of communication devices the unshielded twisted pair wiring plant of an existing home telephone line installation. As with any networking technology, standards have been implemented in order to ensure interoperability between various equipment manufactures and reduce consumer concerns about obsolescence and compatibility. In this regard, many new digital appliances are contemplated that will exploit communication of voice and video across digital networks. Just as there is a critical need for high-speed connections to information and broadband entertainment sources outside the home, there is a growing need to rapidly move this digital data between devices within the home. The Home Phone Line Networking association specifications provide simple, high-speed and cost-effective home networks using a consumer's existing phone line.
Present day architectures capable of supporting home telephone line based network systems include HomePNA version 1; a 1 Mbit/s technology which essentially implements an Ethernetover-telephone line technology and HomePNA version 2, a next generation 10 Mbit/s networking technology.
In order to ensure compatibility with other communication services within the home, such as voice, ISDN, and xDSL data services, the HomePNA 1 Mbit/s technology occupies the passband frequency range between about 3 MHz and about 12 MHz and utilizes passband filters which attenuate frequencies below 3 MHz very rapidly, such that there is no interference with other DSL services or traditional telephone service. Additionally, the HomePNA 10 Mbit/s technology occupies passband frequency range of from about 12 MHz to about 30 MHz. Although operating at a separate frequency band, HomePNA version 2 (10 Mbit/s) devices must share a communication medium (an unshielded twisted wire pair) with any HomePNA version 1 devices that currently exist in the home. In order for the network to function properly, version 1 and version 2 devices must contend for access to the physical wiring medium and, when a version 1 device successfully gains access, the throughput of the network is limited to the data rate attendant upon a generally lower capability version 1 device.
Pertinent to this discussion is the realization that the achievable capacity over most existing premises phone wiring is able to extend upwards to approximately 100 Mbit/s using selective portions of an extended frequency band. The pressure of new applications, combined with ever advancing silicon integration, has resulted in a rapid increase in electronic device performance and the functionality offered thereby. In order to keep up with the evolution of new technological applications, such as higher speed access services, multi-user gains, digital video networking, and the like, home networks must utilize as much of the achievable network capacity as possible, while retaining backward compatibility with devices constructed to conform to earlier standards or specifications.
Accordingly, some means must be provided to enhance the throughput of HomePNA network systems in order to recover the largest degree of available bandwidth attendant to home telephone wiring installations.